I'll take my education in metallurgical engineering for a bit of a run, here, for a bit, instead of decrying that the machines will rule us all. Let's list some positives, here, shall we? Bone grafts made of metal cultures that act like bone. Valves, stems, channels, and prostheses that can have more advanced and adaptive cultures growing on them, to better suit the individual body requirements. With what he was positing about being able to divide hydrogen and oxygen ion, if it comes to fruition, it means we can grow an energy source that provides consistent energy, as the photosynthetic reaction persists.
I should quite like to see the structures under a high powered microscope, and see what kind of microstructure the metals and oxides are exhibiting. Selective penetration could be quite useful in the refractory alloys I'm studying.
EDIT: Reading his other paper, from Jan of last year, he shows an amount of self replication, or at least self-assembly, of a nanowheel. That is actually quite impressive, and given what he is intending to do, the idea of combining them becomes something much more potent.